Technical Field
[0001] The present invention relates to a main group metal complex with cancer cell killing
effect, its preparation method and use in cancer treatment.
Background Art
[0002] Metal complex based small molecule anticancer drugs are important as a type of chemotherapy
drug. Currently, in this field, the studies mostly focus on transition metal complexes
based on such as platinum, ruthenium, and gold. Few attentions have been paid on the
anticancer characteristics of main group metal complexes.
[0003] It has been demonstrated by many studies that main group metal complexes of groups
13, 14 and 15 have medicinal and anticancer activities (
Seng, H-L. and E.R.T Tiekink; Main-Group Medicinal Chemistry Including Li and Bi.
Comprehensive Inorganic Chemistry II, Vol 3. Oxford: Elsevier; 2013, 951-974). Recently, it has been reported that main group metal complexes with cell-killing
ability include indium and tin complexes of thiosemicarbazone (
Galvan-Hidalgo, J.M.; et al. J. Organometal. Chem. 2017, 848, 332-343), gallium trimaltol and tri-8-hydroxyquinoline complex (
Gogna, R.; Madan, E.; Keppler, B.; Pati, U.; Br. J. Pharmacol., 2012, 166, 617), and organogermanium buxicin complexes, etc. (
Yang F., et al.; Bioorg. Med. Chem. Lett., 2013, 23, 5544). Additionally, it has also been disclosed that gallium corrole complexes have significantly
higher photodynamic therapeutic activity than ligands (
M. Pribisko, J. Palmer, R.H. Grubbs, H.B. Gray, J. Termini, P. Lim; PNAS, 2016, 113(16),
E2258).
[0004] However, currently, most of the researches on the anticancer ability of main group
metal complexes are proceeded by way of in vitro experiments. Although, compared with
transition metal complexes such as cisplatin complex, main group metal complexes used
as anticancer drugs still have some problems such as limited treatment ways, taking
effect slowly and low toxicity, current works also show that they have the potential
in the application of anticancer drugs.
[0005] It has been demonstrated by more and more evidences that the medicinal and anticancer
activities of the main group metal complexes of groups 13, 14 and 15 would be affected
by the species and structures of main group metals and their ligands bonded thereto.
Therefore, the seletion of suitable main group metals and their ligands is of great
significance for improving the medicinal and anticancer activities of main group metal
complexes.
Summary of the Invention
[0006] In order to overcome the above-mentioned problems, the inventor of the present invention
have made great efforts and found that: a salicylaldehyde or substituted salicylaldehyde,
a diamine precursor and a main group metal can react to yield a main group metal complex
with anti-tumor effect, which futher has fluorescent properties and thus can be used
as an optical label as well.
[0007] Therefore, according to the present invention, it is to provide:
in a first aspect, a main group metal complex having the structure represented by
Formula I or Formula II as below, or pharmaceutically acceptable salt, solvate, non-covalent
bond compound or prodrug thereof,
which, including its cation, is composed of planar tetradentate Schiff base ligands
and p-block main group metal ions,
wherein, M represents the p-block main group metal;
X represents a diamine residue, and nitrogen atoms on each side of its imine bond
are connected by substituted or unsubstituted C1-12 alkyl or C2-12 alkenyl, or X exists as ortho-substituents of a substituted or unsubstituted aryl
or heterocyclic aryl;
Y is hydrogen, C1-12 alkyl, halogen, halogen-substituted alkyl, cyano, amino, carbonyl, C1-12 alkoxy or
substituted amino;
Z is hydrogen, C1-12 alkyl, halogen, nitro, hydroxyl, mercapto or carboxyl;
R1, R2, R3 and R4 are substituents on the benzene ring of the corresponding ligand, and are each independently
selected from hydrogen, halogen, nitro, hydroxyl, mercapto, carboxyl, amino, cyano,
C1-12 alkyl, C2-12 alkenyl, C2-12 alkynyl, C1-8 alkoxy, C2-8 alkenyloxy, C2-8 alkynyloxy, C1-8 alkylthio, C3-8 heterocyclyl, aryl, C1-8 alkanoyl, C1-8 alkamido, C1-8 alkylsulfonyl, arylsulfonyl, C1-12 alkyl substituted amino or halogen substituted C1-12 alkyl, or two adjacent substituents among R1, R2, R3 and R4 (R1 and R2, R2 and R3 and/or R3 and R4) may form a ring;
in a second aspect, a method for preparing the main group metal complex as disclosed
above, in which a salicylaldehyde or substituted salicylaldehyde represented by Formula
V, a diamine precursor represented by Formula VI, and a main group metal salt MD are
added in an organic solvent L, and the reaction is carried out at a temperature ranging
from 50 to 150 °C for 12 to 24 h, and then the product represented by Formula III
is obtained:

wherein the product represented by Formula IV can be produced according to the following
reaction scheme, in which a ligand represented by Formula VII and a main group metal
salt MD are added in an organic solvent L, and the reaction is carried out at a temperature
ranging from 50 to 150 °C for 12 to 24 h, and then the target complex molecule is
obtained in one step:

in a third aspect, a pharmaceutical composition using the above main group metal complex
as an active ingredient, which futher comprises pharmaceutically acceptable excipient;
in a fourth aspect, a pharmaceutical preparation containing the above main group metal
complex, which can be administrated through gastrointestinal tract or by injection,
wherein the preparations administrated through gastrointestinal tract include tablets,
capsules, oral solutions, oral emulsions, suppositories and granules; and the preparations
administrated by injection include injection solutions, injection emulsions, injection
sustained-release solutions, and injection suspensions;
in a fifth aspect, a use of the above pharmaceutical composition or preparation containing
the main group metal complex having the structure represented by Formula I or Formula
II, or pharmaceutically acceptable salt, solvate, non-covalent bond compound or prodrug
thereof in preparing drugs against cancers, including breast cancer, liver cancer,
lung cancer, melanoma, prostate cancer, colon cancer, colorectal cancer, glioblastoma,
kidney cancer, pancreatic cancer, gastric cancer, lymphoma, cervical cancer, ovarian
cancer, esophageal cancer, nasal cancer, leukemia, breast duct cancer, gallbladder
cancer, testicular cancer, cardia cancer and thyroid cancer, wherein the drugs are
adminstated at a dosage of 0.01 to 200 mg/kg body weight per day or 0.5 to 14 g to
each patient per day;
in a sixth aspect, a use of the main group metal complex having the structure represented
by Formula I or Formula II, or pharmaceutically acceptable salt, solvate, non-covalent
bond compound or prodrug thereof in optical labeling, especially fluorescent labeling,
and preferably in fluorescence imaging, targeted preparations, administation monitoring,
luminescent materials, organic light-emitting diodes, and dye-sensitized solar cells.
[0008] Particularly, the present invention provides a main group metal complex, which is
composed of a planar tetradentate Schiff base ligand, a p-block main group metal ion
and an axial monodentate ligand, and has the structure as shown below:

wherein M represents the p-block main group metal; X represents the diamine residue,
and nitrogen atoms on each side of X are connected by C
1-5 aliphatic chain or substituted aliphatic chain, or exist as ortho substituents of
an aromatic ring; Y is hydrogen or alkyl; R
1, R
2, R
3 and R
4 are each independently selected from hydrogen, halogen, nitro, hydroxyl, amino, substituted
amino, alkyl, alkoxy, halogen substituted alkyl, mercapto or alkylthio, and the two
adjacent substituents, i.e. R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 can form a ring; L represents one or more axial monodentate ligands of halogen, oxygen
coordinating small molecule or nitrogen coordinating small mcolecule; Z is hydrogen
or alkyl.
[0009] M preferably is aluminum, gallium, indium, thallium, germanium, tin, or lead.
[0010] X represents benzene, substituted benzene or pyridine ring, or a C
1-C
3 aliphatic chain or substituted aliphatic chain.
[0011] The halogen is selected from one or more of F, Cl, Br and I; the alkyl group is a
C
1-C
12 alkyl; the substituted amino group is a C
1-C
12 alkyl-substituted amino group; the alkoxy group is C
1-C
8 alkoxy; the halogen-substituted alkyl group is a C
1-C
12 alkyl group substituted by one or more halogens; the alkylthio group is a C
1-C
8 alkyl-substituted mercapto group; the oxygen coordinating small molecule is selected
from one or more of methanol, ethanol, acetone, dimethyl sulfoxide, tetrahydrofuran
and water; the nitrogen coordinating small molecule is selected from one or more of
pyridine, piperidine, n-propylamine, ethylenediamine and ethanolamine.
[0012] R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 form a ring, and represent 1,3-butadiene-1,4-diyl or 1,4-dibutyl together.
[0013] The main group metal complex according to the present invention is one of those as
follows:

[0014] The main group metal complex according to the present invention is prepared following
the reaction scheme below:

[0015] As shown in the above reaction scheme, the salicylaldehyde or substituted salicylaldehyde,
the diamine precursor, and the main group metal salt MD are added in the organic solvent
L, and the reaction is carried out at a temperature of 50 to 150 °C for 12 to 24 h,
and then the complex represented by formula I can be obtained in one step. X, Y, M,
L, R
1, R
2, R
3 and R
4 are same as those described above.
[0016] Alternatively, the main group metal complex according to the present invention is
prepared following the reaction scheme below:

[0017] As shown in the above reaction scheme, the complex and the main group metal salt
MD are added in the organic solvent L, and the reaction is carried out at a temperature
of 50 to 150 °C for 12 to 24 h, and then the complex represented by formula II can
be obtained in one step. X, Y, Z, M, L, R
1, R
2, R
3 and R
4 are same as those described above.
[0018] The organic solvent used in the above two reactions can be methanol, ethanol or acetonitrile.
After the reaction, recrystallization will be carried out with acetonitrile/ether
based solvent to make the complex solid precipitate out of the system.
[0019] The main group metal complex according to the present invention can be used to prepare
the anticancer drugs.
[0020] The main group metal complex, and its preparation method and use provided according
to the present invention have the following beneficial effects, i.e.
- 1) the main group metal complex according to the present invention shows high cytotoxicity
to a variety of cancer cell lines, has selective killing effect, and is more effective
than the conventional metal anticancer drugs;
- 2) the main group metal complex according to the present invention has excellent fluorescence
properties and can be used as an optical label for fluorescent labeling, especially
single- or double-photon(s) fluorescent labeling, such as in vivo imaging tracking,
targeted preparations, administation monitoring, and luminescent materials;
- 3) the main group metal complex according to the present invention can be easily obtained
by the simple preparation method thereof.
Desciption of Figures
[0021]
Fig. 1 shows the median lethal concentrations of the complex against different cancer
cell lines according to Experiment 1 ;
Fig.2 shows the cytotoxicity curve of the complex against the human cervical cancer
cell line HeLa according to Experiment 1 ;
Fig.3 shows the cell imaging diagram according to Experiment 3;
Fig.4 shows the fluorescence image obtained in the mouse in vivo experiment according
to Experiment 4;
Fig.5A and 5B show the changes in volume and mass of the tumor after treatment in
the in vivo tumor suppression experiment according to Experiment 5, respectively;
Fig.6 shows the weight change curve of nude mice after treatment in the in vivo tumor
suppression experiment according to Experiment 5;
Fig.7D shows the H&E staining diagram of tumor tissue in the in vivo tumor suppression
experiment according to Experiment 5; Fig.7E shows black and white NMR image and color
NMR image of tumor location in each experimental group; Fig.7F shows the standard
deviation of the tumor tissue change in each group of E;
Fig.8 shows the results of hematological analysis in the in vivo tumor suppression
experiment according to Experiment 5;
Fig.9 shows the H&E staining image of major organs in the in vivo tumor suppression
experiment according to Experiment 5.
Desciption of the Preferred Embodiments
[0022] Hereafter, the present invention will be described in detail, and the features and
the advantages of the invention thus will become much clearer and obvious with the
following exemplary desciption.
[0023] The term "exemplary" herein means "taking an example, an embodiment, or an illustration."
Any embodiment described exemplarily herein should not be considered as being superior
or better than other embodiments.
[0024] The present invention provides a main group metal complex having the structure represented
by Formula I or Formula II as below, or pharmaceutically acceptable salt, solvate,
non-covalent bond compound or prodrug thereof,
which, including its cation, is composed of planar tetradentate Schiff base ligands
and p-block main group metal ions,
wherein, M represents the p-block main group metal;
X represents a diamine residue, and nitrogen atoms on each side of its imine bond
are connected by substituted or unsubstituted C1-12 alkyl or C2-12 alkenyl, or X exists as ortho-substituents of a substituted or unsubstituted aryl
or heterocyclic aryl;
Y is hydrogen, C1-12 alkyl, halogen, halogen-substituted alkyl, cyano, amino, carbonyl, C1-12 alkoxy or
substituted amino;
Z is hydrogen, C1-12 alkyl, halogen, nitro, hydroxyl, mercapto or carboxyl;
R1, R2, R3 and R4 are substituents on the benzene ring of the corresponding ligand, and are each independently
selected from hydrogen, halogen, nitro, hydroxyl, mercapto, carboxyl, amino, cyano,
C1-12 alkyl, C2-12 alkenyl, C2-12 alkynyl, C1-8 alkoxy, C2-8 alkenyloxy, C2-8 alkynyloxy, C1-8 alkylthio, C3-8 heterocyclyl, aryl, C1-8 alkanoyl, C1-8 alkamido, C1-8 alkylsulfonyl, arylsulfonyl, C1-12 alkyl substituted amino or halogen substituted C1-12 alkyl, or two adjacent substituents among R1, R2, R3 and R4 (R1 and R2, R2 and R3 and/or R3 and R4) may form a ring.
[0025] In this invention, the p-block main group metals refer to metal elements among the
p-block main group elements defined according to the current periodic table, and generally
refer to the metals of group 13, i.e. aluminum, gallium, indium, thallium and the
metals of group 14, i.e. germanium, tin, lead.
[0026] M in Formula I or Formula II is one of aluminum, gallium, indium, thallium, germanium
or tin, preferably is one of aluminum, gallium, indium, thallium or germanium, and
most preferably is one of aluminum, gallium, indium or germanium.
[0027] In this invention, unless otherwise stated, the carbon atoms of the alkyl, alkenyl,
alkynyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, heterocyclyl, aryl, heterocyclic
aryl, alkanoyl, alkamido, alkylsulfonyl, arylsulfonyl, alkylamino and hydrocarbyl
substituted amino can be substituted or not substituted by halogen, nitro, hydroxyl,
mercapto, carboxyl, amino, cyano or carbonyl.
[0028] The term "alkyl" herein refers to a linear, branched or cyclic saturated hydrocarbon
group, for example, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, cyclohexyl
and 2-ethyl-4 propyl-cyclohexyl. C
1-12 refers to a hydrocarbon chain with 1-12 carbon atoms.
[0029] The term "alkenyl" herein refers to a hydrocarbon group containing an alkenyl group
in a linear, branched or cyclic hydrocarbon chain, and the carbon atom on the alkenyl
can be connected or not connected to the carbon atom on the phenyl of the ligand,
for example, vinyl, 1-allyl, 1-phenyl-allyl, and 2-methpropenyl. Similarly, C
2-12 alkenyl refers to the alkenyl group with 2-12 carbon atoms.
[0030] The term "alkynyl" herein refers to a linear, branched or cyclic hydrocarbon group
including an alkynyl group, and the carbon atom on the alkynyl can be connected or
not connected to the carbon atom on the phenyl of the ligand, for example, propynyl,
propargyl, 2-methylbutynyl. Similarly, C
2-12 alkynyl refers to the alkynyl group with 2-12 carbon atoms.
[0031] The term "alkoxy" herein refers to the alkyl including an oxyether group, such as
methoxy group, ethoxy group, and propoxy group. C
1-8 alkoxy refers to the alkoxy group with 1-8 carbon atoms.
[0032] The term "alkenyloxy" herein refers to a linear, branched or cyclic hydrocarbon group
with an alkenyl group including an oxyether group. C
2-8 alkenyloxy refers to the alkenyloxy group with 2-8 carbon atoms.
[0033] The term "alkynyloxy" herein refers to a linear, branched or cyclic hydrocarbon group
with an alkynyl group including an oxyether group. C
2-8 alkynyloxy refers to the alkynyloxy group with 2-8 carbon atoms.
[0034] The term "alkylthio" herein refers to the alkyl including a thioether group, such
as methylthio, ethylthio, and propylthio. C
1-8 alkylthio refers to the alkylthio group with 1-8 carbon atoms.
[0035] The term "heterocyclyl" herein refers to a stable 3-8 membered saturated cyclic group
containing one or more heteroatom(s), which can be connected or not connected to the
benzene of the ligand, preferably connected. Typical heteroatoms include oxygen, sulfur
and nitrogen. For example, it can be tetrahydropyrrolyl, quinoline, thiophene, furan
and the like. C
3-8 heterocyclic group refers to the heterocyclic group with 3-8 carbon atoms.
[0036] The term "aryl" herein refers to an aromatic ring containing a phenyl group, generally
is benzene, naphthalene, anthracene or phenanthrene, and preferably is benzene and
naphthalene.
[0037] The term "heterocyclic aryl" herein refers to a monoaromatic ring or polyaromatic
ring group including one or more heteroatom(s), preferably a 5-10 membered ring. The
polyaromatic ring group may be a double monoaromatic ring, a benzo monoaromatic ring
or a condensed aromatic ring group. For example, the aryl group may be furan, pyridine,
thiophene, imidazole, pyrrole, pyridazine, pyrazine, benzopyrrole, benzofuran, benzisoquinoline,
pyrazinopyridazine, or the like.
[0038] The term "alkanoyl" herein refers to the alkyl including an acyl group. C
1-8 alkanoyl group refers to the alkanoyl group with 1-8 carbon atoms.
[0039] The term "alkamide" herein refers to the alkyl including an alkamide group. C
1-8 alkamide group refers to the alkamide group with 1-8 carbon atoms.
[0040] The term "alkylsulfonyl" herein refers to the alkyl including an alkylsulfonyl group.
C
1-8 alkylsulfonyl group refers to the alkylsulfonyl group with 1-8 carbon atoms.
[0041] The term "arylsulfonyl" herein refers to the aryl including a sulfonyl group.
[0042] The term "alkyl-substituted amino" herein refers to an amino group substituted by
the alkyl group, such as methylamino, ethylamino, dimethylamino, and diethylamino.
C
1-12 alkylamino group refers to the alkylamino group with 1-12 carbon atoms in the alkyl
substituent.
[0043] Further, the nitrogen atoms on each side of X are connected by an aliphatic chain
or a substituted aliphatic chain with a carbon number of 1 to 5, or exist as ortho
substituents of the aromatic ring.
[0044] Preferably, X in Formula I or Formula II is selected from -CH
2-, -CH
2-CH
2-, -CH(CH
3)-CH
2-, -CH(CN)-CH(CN)-, -CH(CN)-CH
2-, -CH
2(Cl)-CH(CN)-, -CH
2(OH)-CH(CN)-, - CH
2(Cl)-CH
2-, -CH
2(OH)-CH
2-, -CH=CH-, -CO-CH(CN)-, -C(CN)=C(CN)-, -CH=C(CN)-, -CH=C(Cl)-, -CH=CH-CH=CH-, -CH=C(CN)-CH=CH-,
-CH=C(NH
3)- or -CO-CH
2-, or acts as an ortho-disubstituted group of the substituted or unsubstituted benzene,
naphthalene, anthracene, phenanthrene, pyridine, imidazole, pyrrole, thiophene, furan,
benzopyrrole or benzofuran. When X is a cyclic group, it is connected to the imino
group of the corresponding ligand through two adjacent cyclic backbone atoms.
[0045] More preferably, X is selected from -CH
2-, -CH
2-CH
2-, -CH(CN)-CH(CN)-, -CH(CN)-CH
2-, -CH
2(Cl)-CH(CN)-, -CH
2(Cl)-CH
2-, -CH
2(OH)-CH
2-, -CH=CH-, -C(CN)=C(CN)-, - CH=C(CN)-, -CH=C(Cl)- or -CH=C(NH
3)-, or acts as an ortho-disubstituted group of benzene, pyridine, benzopyridine, imidazole,
furan, cyano-substituted benzene, naphthalene, cyano-substituted naphthalene.
[0046] In some preferred embodiments, X in Formula I and the two imino groups in the corresponding
ligand may form a conjugated structure.
[0047] In these embodiments, X may be selected from ethylene, cyano-substituted ethylene,
1,3-butadiene, cyano-substituted 1,3-butadiene, benzene, pyridine, benzopyridine,
naphthalene, cyano-substituted naphthalene.
[0048] Preferably, X in Formula I or Formula II is selected from ethylene, cyano-substituted
ethylene, 1,3-butadiene, benzene, cyano-substituted benzene, pyridine or cyano-substituted
pyridine.
[0049] Most preferably, X is selected from -CH=CH-, -C(CN)=C(CN)-, -CH=C(CN)-, - CH=C(CN)-CH=CH-,
-CH=C(NH
3)- or -CO-CH
2-, or acts as an ortho-disubstituted group of those as follows:

[0050] In some preferred embodiments, X is -C(CN)=C(CN)-.
[0051] In some preferred embodiments, X is phenyl group.
[0052] In some preferred embodiments, X is 4-cyano substituted phenyl group.
[0053] In some preferred embodiments, X is 4,5-dicyano substituted phenyl group.
[0054] In some preferred embodiments, X is

[0055] In some embodiments, X in Formula I or Formula II is a substituted or unsubstituted
saturated alkyl group. In these embodiments, X is preferably selected from -CH
2-, - CH
2-CH
2-, -CH
2(Cl)-CH
2-, -CH(CN)-CH(CN)-, -CH
2(OH)-CH
2- or -CH
2(CH
3)-CH
2-, and more preferably is -CH
2-, -CH
2-CH
2-, -CH
2(Cl)-CH
2- or -CH
2(CH
3)-CH
2-.
[0056] Further, Y in Formula I or Formula II is hydrogen, halogen, cyano, C
1-4 alkyl or C
1-4 alkoxy, wherein halogen includes F, Cl, Br and I.
[0057] When Y in Formula I or Formula II is an alkyl group, it is more preferably a C
1-3 alkyl.
[0058] Preferably, Y is hydrogen, halogen, cyano, methyl, ethyl, isopropyl, methoxy, ethoxy,
halogen-substituted C
1-3 alkyl or halogen-substituted C
1-3 alkoxy.
[0059] More preferably, Y is hydrogen, halogen, cyano, methyl or methoxy.
[0060] Z is hydrogen, C
1-10 alkyl, halogen, nitro, hydroxyl, mercapto or carboxyl. Preferably, Z is hydrogen,
C
1-6 alkyl, halogen, nitro, hydroxyl, mercapto or carboxyl.
[0061] In some embodiments, Z is hydrogen.
[0062] In the main group metal complex according to the present invention, R
1, R
2, R
3 and R
4 are each independently selected from hydrogen, halogen, nitro, hydroxyl, mercapto,
carboxyl, amino, cyano, C
1-12 alkyl, C
2-12 alkynyl, C
2-12 alkynyl, C
1-8 alkoxy, C
2-8 alkenyloxy, C
2-8 alkynyloxy, C
1-8 alkylthio, C
3-8 heterocyclyl, aryl, C
1-8 alkanoyl, C
1-8 alkamido, C
1-8 alkylsulfonyl, arylsulfonyl, N,N-bis(C
1-8 alkyl)amino, N-(C
1-6 alkyl)-N-(C
1-6 alkyl)amino, N-(C
1-6 alkyl)-N-(C
1-6 alkynyl)amino, N,N-diarylamino, N-(C
1-6 alkyl)-N-arylamino, N-(C
1-6 alkyl)-N-heterocyclylamino, -CF
3-, -ClCH
2-, -ClCH
2-CH
2-, (CH
3)
2C(CH
2Cl)-, CH
2-CH
2Cl-CH(CH
3)
2- or halogen-substituted C
3-6 cyclic alkyl group. C
3-6 cyclic alkyl group includes halogen-substituted cyclohexyl, halogen-substituted cyclopentyl,
and halogen-substituted methylcyclopentyl.
[0063] Preferably, R
1, R
2, R
3 and R
4 in Formula I or Formula II are each independently selected from hydrogen, fluorine,
chlorine, bromine, iodine, nitro, hydroxyl, mercapto, amino, cyano, C
1-5 alkyl, C
1-4 alkylthio, C
1-4 alkoxy, C
1-8 alkylamino, N,N-bis(C
1-6 alkyl)amino, N-(C
1-6 alkyl)-N-(C
1-6 alkyl)amino, N-(C
1-6 alkyl)-N-(C
3-6 alkynyl)amino, C
3-8 unsaturated heterocyclic group, C
3-8 saturated heterocyclic group, halogen substituted C
5-6 cyclic alkyl or halogen-substituted C
1-6 alkyl.
[0064] In some preferred embodiments, R
1, R
2, and R
4 in Formula I or Formula II are each independently selected from hydrogen, cyano,
mercapto, C
2-4 alkylthio or C
1-5 alkyl.
[0065] In some preferred embodiments, in Formula I or Formula II, R
1 is hydrogen, R
4 is hydrogen, cyano or C
1-5 alkyl, and R
2 is hydrogen, mercapto, C
2-4 alkylthio or C
1-5 alkyl.
[0066] In some preferred embodiments, in Formula I or Formula II, R
1 and R
2 are hydrogen, and R
4 is mercapto or C
2-4 alkylthio.
[0067] In some preferred embodiments, in Formula I or Formula II, R
1 and R
4 are hydrogen, and R
2 is mercapto or C
2-4 alkylthio.
[0068] In some preferred embodiments, in Formula I or Formula II, R
1, R
2 and R
4 are hydrogen.
[0069] R
3 in Formula I or Formula II is selected from hydrogen, fluorine, chlorine, amino,
C
1-8 alkylamino, C
1-4 alkoxy, N,N-bis(C
1-8 alkyl)amino, N-(C
1-6 alkyl)-N-(C
1-4 alkyl)amino, N-(C
1-4 alkyl)-N-(C
3-5 alkynyl)amino, C
3-8 unsaturated nitrogen heterocyclyl or C
3-8 saturated nitrogen heterocyclyl.
[0070] Preferably, R
3 in Formula I or Formula II is selected from hydrogen, C
1-4 alkoxy, N,N-bis(C
1-5 alkyl)amino, N-(C
1-4 alkyl)-N-(C
1-2 alkyl)amino, N-(C
1-4 alkyl)-N-(C
3-5 alkynyl)amino, or C
3-5 saturated nitrogen heterocyclyl.
[0071] More preferably, R
3 in Formula I or Formula II is selected from hydrogen, methoxy, ethoxy, isopropoxy,
N,N-dimethylamino, N,N-diethylamino, N,N-dipropylamino, N-(2-methyl butyl) amino,
N-butyl-N-methylamino, N-ethyl-N-methylamino, N-butyl-N-ethylamino, N-propargyl-N-methyl
amino, N-alkynylbutyl-N-ethylamino, tetrahydropyrrole, hydrogenated pyridine or hydrogenated
imidazole.
[0072] In some preferred embodiments, R
3 in Formula I or Formula II is N,N-dimethylamino, and R
4 is C
2-4 alkylthio.
[0073] In some preferred embodiments, R
3 in Formula I or Formula II is N,N-diethylamino, and R
4 is mercapto, C
1-4 alkyl or C
1-4 alkoxy.
[0074] In some preferred embodiments, R
3 in Formula I or Formula II is hydrogen, methoxy, N,N-diethylamino, N,N-dimethylamino,
N-methyl-N-n-butylamino, N-methyl-N-propargylamino or tetrahydropyrrole, and R
4 is hydrogen.
[0075] In some preferred embodiments, R
1, R
2, R
3 and R
4 in Formula I or Formula II are hydrogen.
[0076] In the main group metal complex according to the present invention, two adjacent
substituents among R
1, R
2, R
3 and R
4 (R
1 and R
2, R
2 and R
3 and/or R
3 and R
4) may also form a ring.
[0077] When R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 form a ring, they represent, for example, 1,3-butadiene-1,4-diyl or 1,4-dibutyl,
etc., and are combined with the benzene ring to form naphthalene or tetrahydronaphthalene,
etc.
[0078] In some embodiments, in Formula I or Formula II, R
2 and R
3 or R
3 and R
4 preferarbly form a ring as follows:

[0079] In some embodiments, in Formula I or Formula II, both R
2 and R
3, and, R
3 and R
4 form rings, preferarbly as follows:

[0080] Preferarbly, the main group metal complex having the structure represented by Formula
I or Formula II further has ligands represented by Formula III and Formula IV as below:

[0081] Wherein L represents one or more axial monodentate ligands, including anionic ligands
and neutral ligands. L may also be a non-coordinating anion. Preferably, the anionic
ligand includes halogen ions such as fluorine, chlorine, bromine, iodide ions, and
acetate ions. The neutral ligand is an oxygen coordinating or nitrogen coordinating
ligand, preferably derived from a solvent molecule.
[0082] The oxygen coordinating solvent molecule is one or more selected from methanol, ethanol,
acetone, dimethyl sulfoxide, tetrahydrofuran, water, isopropanol, glycerin, formaldehyde,
acetic acid, formic acid, ether and dimethyl sulfoxide. The nitrogen coordinating
solvent molecule is one or more selected from pyridine, piperidine, n-propylamine,
ethylenediamine, ethanolamine, dimethylformamide, acetonitrile, ammonia and triethylamine.
[0083] Preferably, L is selected from fluoride, chloride, bromide, acetate, methanol, ethanol,
isopropanol, acetone, dimethylsulfoxide, dimethylformamide, pyridine or acetonitrile.
[0084] Further, the present invention provides a main group metal complex, which is composed
of a planar tetradentate Schiff base ligand, a p-block main group metal ion and an
axial monodentate ligand. In Formula III and Formula IV, M represents the p-block
main group metal; X represents the diamine residue, and nitrogen atoms on each side
of X are connected by C
1-5 aliphatic chain or substituted aliphatic chain, or X exists as ortho substituents
of an aromatic ring such as benzene, substituted benzene, pyridine; Y is hydrogen
or alkyl; R
1, R
2, R
3 and R
4 are substituents on benzene of the corresponding ligand backbone, and each independently
selected from hydrogen, halogen, nitro, hydroxyl, amino, substituted amino, alkyl,
alkoxy, halogen substituted alkyl, mercapto or alkylthio, and two adjacent substituents,
i.e. R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 can form a ring; L represents one or more axial monodentate ligands of halogen, oxygen
coordinating small molecule or nitrogen coordinating small mcolecule; and Z in Formula
II is hydrogen or alkyl.
[0085] Preparably, M is one of group 13 metals (aluminum, gallium, indium, thallium) or
group 14 metals (germanium, tin, lead).
[0086] X is an aromatic ring such as benzene, substituted benzene and pyridine, or a C
1-C
3 aliphatic chain or substituted aliphatic chain, wherein the substituent of the aliphatic
chain is, for example, cyano. In some embodiments, X is -CH
2-CH
2-, ortho-disubstituted benzene, -C(CN)=C(CN)-, or the like.
[0087] Halogen includes F, Cl, Br and I.
[0088] The alkyl group is preferably C
1-C
12 alkyl, more preferably C
1-C
6 alkyl, such as methyl, ethyl, propyl, isopropyl, butyl.
[0089] The substituted amino group is preferably C
1-C
12 alkyl-substituted amino group, more preferably C
1-C
6 alkyl-substituted amino group, such as methylamino, ethylamino, dimethylamino, diethylamino.
[0090] The alkoxy group is preferably C
1-C
8 alkoxy, more preferably C
1-C
4 alkoxy, such as methoxy, ethoxy, propoxy.
[0091] The halogen-substituted alkyl group is preferably C
1-C
12 alkyl group substituted by one or more halogens, more preferably C
1-C
6 alkyl group substituted by one or more halogens, such as trifluoromethyl.
[0092] The alkylthio group is preferably C
1-C
8 alkyl-substituted mercapto group, more preferably C
1-C
4 alkyl-substituted mercapto group, such as methylthio, ethylthio, propylthio.
[0093] When R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 form a ring, they represent 1,3-butadiene-1,4-diyl, 1,4-dibutyl, or the like, and
are combined with the benzene ring to form naphthalene, tetrahydronaphthalene, or
the like.
[0094] The oxygen coordinating solvent molecule is for example methanol, ethanol, acetone,
dimethyl sulfoxide, tetrahydrofuran, water, or the like. The nitrogen coordinating
solvent molecule is for example pyridine, piperidine, n-propylamine, ethylenediamine,
ethanolamine, or the like.
[0095] The typical main group metal complexs includes for example those as below:

[0096] In the complex I, M is indium, L is chlorine, X is -CH
2-CH
2-, Y is hydrogen, and the salicylaldehyde residue has no modification on the benzene
ring.
[0097] In the complex II, M is gallium, L is chlorine, X is ortho-disubstituted benzene,
Y is hydrogen, and the modification on the benzene ring of the salicylaldehyde residue
is a diethylamino at position R
3.
[0098] In the complex III, M is germanium, L is two chlorines, X is -C(CN)=C(CN)-, Y is
hydrogen, and the modification on the benzene ring of the salicylaldehyde residue
is a methoxy at position R
3.
[0100] The main group metal complex having the structure represented by Formula I or Formula
II according to the present invention can also be present in the form of pharmaceutically
acceptable salt, as shown in Formula V or Formula VI below:

[0101] The salt of the compound according to the present invention refers to a non-toxic
pharmaceutically acceptable salt, generally an inorganic acid salt or an organic acid
salt. In Formula V or Formula VI, D
- represents an acid radical of an inorganic acid or an organic acid forming a salt.
[0102] Typical organic or inorganic acids include hydrochloric acid, hydrobromic acid, hydroiodic
acid, perchloric acid, nitric acid, acetic acid, sulfuric acid, propionic acid, glycolic
acid, lactic acid, succinic acid, maleic acid, fumaric acid, malic acid, Tartaric
acid, citric acid, benzoic acid, mandelic acid, methanesulfonic acid, benzenesulfonic
acid, oxalic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, cyclohexaminesulfonic
acid, salicylic acid or trifluoroacetic acid.
[0103] Preferably, the inorganic acid or the organic acid is selected from hydrochloric
acid, hydrobromic acid, perchloric acid, nitric acid, acetic acid, sulfuric acid,
lactic acid, succinic acid, maleic acid, fumaric acid, malic acid, Tartaric acid,
citric acid, benzoic acid, methanesulfonic acid, benzenesulfonic acid, oxalic acid,
p-toluenesulfonic acid, trifluoromethanesulfonic acid, or salicylic acid.
[0104] More preferably, the inorganic acid or the organic acid is selected from hydrochloric
acid, nitric acid, acetic acid, sulfuric acid, lactic acid, succinic acid, maleic
acid, tartaric acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic
acid, trifluoromethanesulfonic acid or salicylic acid.
[0105] In some preferred embodiments, the pharmaceutically acceptable salt of the main group
metal complex having the structure represented by Formula I or Formula II is hydrochloride,
nitrate or triflate.
[0106] The main group metal complex having the structure represented by Formula I or Formula
II according to the present invention can also be present in the form of a pharmaceutically
acceptable solvate, non-covalent compound or prodrug.
[0107] The present invention further provides a method for preparing the main group metal
complex having the structure represented by Formula I or Formula II, especially the
structure represented by Formula III or Formula IV.
[0108] Wherein a salicylaldehyde or substituted salicylaldehyde represented by Formula V,
a diamine precursor represented by Formula VI, and a main group metal salt MD are
added in an organic solvent L, and the reaction is carried out at a temperature of
50 to 150 °C for 12 to 24 h, and then the target complex molecule is obtained in one
step:

[0109] Alternatively, asalicylaldehyde or substituted salicylaldehyde, a diamine precursor
and a main group metal salt ML as shown below are added in an organic solvent, and
react at a temperature of 50-150 °C for 12-24 h, and then the target complex molecule
is obtained in one step. Most preferably, the reaction is carried out at 90 °C for
24 h. The organic solvent can be for example methanol, ethanol, acetonitrile, or the
like. The reaction proceeds according to the following reaction scheme:

[0110] The complex represented by Formula IV can be obtained following the reaction scheme
as below. Particulatly, a ligand represented by Formula VII and a main group metal
salt MD are added in an organic solvent L, and react at a temperature of 50-150 °C
for 12-24 h, and then the target complex molecule is obtained in one step.

[0111] Alternatively, a ligand represented by Formula VII and a main group metal salt ML
are added in an organic solvent, and react at a temperature of 50-150 °C for 12-24
h, and then the target complex molecule is obtained in one step. The organic solvent
can be methanol, ethanol, acetonitrile, or the like.

[0112] According to the present invention, MD represents a metal salt. Further, when M is
M
2+, L is a neutral ligand, such as methanol, acetonitrile; when M is M
3+ or M
4+, L = D, which is an anionic ligand, such as chloride ion, bromide ion, acetate ion,
or the like.
[0113] During the reaction, the organic solvent can be any selected from acetone, dimethylformamide,
dimethylsulfoxide, pyridine, methanol, ethanol and acetonitrile. Preferably, the reaction
is carried out at a temperature of 90-150 °C for 12-24 h.
[0114] The preparation method further comprises a post-treatment. Typically, the post-treatment
is achieved by recrystallizating to make the product precipitate from the reaction
system.
[0115] In a preferred embodiment, the post-treatment is carried out via recrystallization
using the acetonitrile/ether solvent system, and consequently the complex solid can
precipitate out of the system.
[0116] The main group metal complexes having the structure represented by Formula I or Formula
II according to the present invention have significant toxicity and killing effect
on various cancer cell lines. The median lethal concentration in 24 hours is generally
below 2 µM. The median lethal concentration difference of these complexes against
normal cell lines and cancer cell lines can reach up to 10 times, so it is believed
that they have selective killing effect on cancer cell lines.
[0117] Among them, the representative complex 1 has significant toxicity to a variety of
cancer cell lines, and its median lethal concentration in 24 hours is generally below
2 µM. The median lethal concentration of complex 11 against human malignant melanoma
cells is lowest and can be about 70 nM.
[0118] Some of the main group metal complexes according to the present invention have stronger
fluorescence emission characteristic. Through confocal fluorescence imaging in combination
with experimental methods such as protein immunoblotting, mRNA gene chip and proteomics
research, the action mechanism of such complexes have been studied. We found that
after these complexes enter the cells by passive diffusing, the enzyme activity of
the protein disulfide isomerase family in the endoplasmic reticulum is inhibited,
the normal protein folding process is hindered, and a series of unfolded protein reactions
including endoplasmic reticulum stress are triggered, by which the state and function
of mitochondrias are affected, causing the swelling of mitochondrias and the membrane
potential of the mitochondrial inner membrane degraded, subsequently, active oxygen
species are generated , and ultimately cell homeostasis is destroyed, leading to the
cell death. That is obviously different from the cancer cell killing mechanism of
platinum-based cancer drugs that target nuclear DNA such as cisplatin.
[0119] The main group metal Schiff base complexes according to the present invention have
obvious killing effects on cancer cells. It has been demonstrated by experiments that
the median lethal concentrations against cancer cell lines in 24 hours of these complexes
are significantly lower than those of the main group metal complexes reported in the
literatures, even some transition metal complexes with anticancer activity including
cisplatin. This means that the complexes according to the present invention have the
potential to be used as small molecule anticancer drugs in clinical treatment.
[0120] Thus, the present invention further provides a pharmaceutical composition, comprising
as an active ingredient the main group metal complex with the structure represented
by Formula I or Formula II or the main group metal complex having the structure represented
by Formula I or Formula II obtained by the aforementioned preparation method, and
pharmaceutically acceptable excipients. The pharmaceutically acceptable salt, solvate,
non-covalent compound or prodrug of the main group metal complex having the structure
represented by Formula I or Formula II can also be used as the active ingredient of
the pharmaceutical composition.
[0121] Depending on its administration method, the pharmaceutical composition can be prepared
into various forms with a predetermined dosage of the active ingredient, for example,
common tablets, capsules, oral solutions, oral emulsions, suppositories, or granules
administrated through the gastrointestinal tract. The pharmaceutical composition according
to the present invention can also be administered by injection, including intravenous
injection, arterial injection, intramuscular injection and spinal cavity injection.
By a controlled release manner or via a delivery device, the pharmaceutical composition
can be prepared into, for example, common dosage forms, such as injection solution,
injection emulsion, injection sustained-release solution, or injection suspension.
[0122] According to the application form of the pharmaceutical composition, the excipients
in the composition should be inactive ingredients which are applicable to the administration
route or way and are non-toxic to the human body.
[0123] The excipients can be solid, liquid or gas form. Solid excipients, for example, include
sodium chloride, glucose, sodium lactate, poloxamer, sodium lauryl sulfate, sodium
dodecylbenzene sulfonate, sodium hydroxide, triethylamine, sodium carbonate, sodium
bicarbonate, sucrose , sodium carboxymethyl cellulose, gelatin, xanthan gum, povidone,
starch, magnesium stearate, sodium carboxymethyl starch, talc and pectin. Liquid excipients,
for example, include ethylene glycol, hydrochloric acid, sulfuric acid , phosphoric
acid, acetic acid, triethylamine, water, ethanol, isopropanol, peanut oil, soybean
oil, syrup and glycerin. Gas excipients, for example, include carbon dioxide and nitrogen.
[0124] The pharmaceutical composition according to the present invention can be a sterile
system administrated by injection, wherein the active ingredient with one or more
excipients can be prepared as a sterile solution or dispersion system, or prepared
as sterile powder which can be converted into a sterile solution for injectiona immediately
before use. It can be prepared by mixing water, ethanol, or appropriate excipients,
such as isotonic regulators of blood, surfactants, and antioxidants. The pharmaceutical
composition should be stable during preparation and storage. Preferably, the dosage
of the active ingredient in the unit dosage form is between 0.01 mg and 10 g, and
based on the total weight of the pharmaceutical composition, the active ingredient
in the sterile system is 0.01 wt% -10 wt%.
[0125] The pharmaceutical composition according to the present invention can be an oral
solid, and prepared by mixing the active ingredient and excipients, such as fillers,
disintegrants, binders and lubricants and molding by suitable devices.
[0126] The pharmaceutical composition can be an oral liquid, and prepared by dissolving
or dispersing the active ingredient in a solvent and then mixing with excipients,
such as surfactants, thickeners, emulsifiers, preservatives.
[0127] In addition to the pharmaceutical compositions in various forms mentioned above,
the active ingredient and suitable excipients can also be prepared for local administration,
for example, rectal administration, transdermal administration, nasal administration,
etc.
[0128] The present invention also provides a use of the main group metal complexes having
the structure represented by Formula I or Formula II, and pharmaceutically acceptable
salt, solvate, non-covalent compound or prodrug thereof, or their pharmaceutical compositions
for preparing cancer drugs.
[0129] Preferably, they are used for preparing drugs against the cancers including breast
cancer, liver cancer, lung cancer, melanoma, prostate cancer, colon cancer, colorectal
cancer, glioblastoma, kidney cancer, pancreatic cancer, gastric cancer, lymphoma,
cervical cancer, ovarian cancer, esophageal cancer, nasal cancer, leukemia, breast
duct cancer, gallbladder cancer, testicular cancer, cardia cancer and thyroid cancer.
[0130] Depending on the patient's age, weight, health status, diet, administration route,
combination medication, treatment time, etc., the specific dosage of the drug may
vary individually. Gernally, in the treatment of the above diseases, the dose level
of the drug is 0.01-200 mg/kg body weight per day, or 0.5-14 g per patient per day.
[0131] The present invention also provides a use of the main group metal complex having
the structure represented by Formula I or Formula II, and salt, solvate, non-covalent
compound or precursor thereof for optical labeling.
[0132] The main group metal complex having the structure represented by Formula I or Formula
II has a stronger fluorescence emission, and thus can be prepared as a fluorescent
maker to use for fluorescent labeling, especially single and two-photon fluorescent
labeling.
[0133] It has been found by studies that the complex according to the present invention
has a fluorescence color that is significantly different from the autofluorescence
color of biological systems. For example, the complex having the structure shown in
Example 1 according to the present invention has a red fluorescence emission and the
fluorescence quantum yield is up to 50 %, which is obviously distinguished from the
autofluorescence of biological systems.
[0134] Therefore, the main group metal complex having the structure represented by Formula
I or Formula II can be used as imaging probes.
[0135] Further, in view of the cell level, the main group metal complex according to the
present invention with such fluorescence characteristic can be used to study the cell
activities, such as cellular location, cellular uptake, and cell physiological changes
downstream.
[0136] In view of the living organisms, the main group metal complex according to the present
invention with such fluorescence characteristic can be used for in vivo imaging. By
studying the distribution of the main group metal complex in vivo, targeted drug delivery
can be performed much well, so as to deliver the predetermined active ingredient,
such as the main group metal complex, and salt, solvate or prodrug thereof, or the
main group metal complex together with other ingredients and chemical modifications
to the location around the tumor tissue.
[0137] In a preferred embodiment, the main group metal complex having the structure represented
by Formula I or Formula II can be used to prepare targeted drugs.
[0138] In the process of clinical application, it also can be expected to use the main group
metal complex with the fluorescence characteristic for drug monitoring, so as to evaluate
the effectiveness and individual differences of drugs based on the distribution of
drugs in the body.
[0139] The main group metal complex having the structure represented by Formula I or Formula
II according to the present invention has an excellent light-emitting property, and
thereby can also be used as a light-emitting small molecule material in a non-biological
system in the fields such as material scicence, OLED (organic light emitting diode),
dye-sensitized solar cells.
Examples
Example 1
[0140] The complex 1 was prepared as follows:

[0141] The substituted salicylaldehyde, the diamine precursor and indium trichloride corresponding
to complex 1 were placed in acetonitrile, and then reacted at 90 °C under reflux for
24 h. After stopping the reflux, a large amount of ether was added to the system,
so that a light yellow solid was precipitated. Then, the precipitated solid was filtrated,
collected and washed with ether, and consequently the pure complex 1 was yielded.
Characterization:
[0142] The structure of the complex 1 was characterized by hydrogen nuclear magnetic resonance
spectrum, carbon spectrum, high-resolution mass spectrometry and infrared spectroscopy,
and the photophysical properties of the complex 1 were characterized by ultraviolet-visible
absorption spectrometer and fluorescence spectrometer.
[0143] 1H NMR (400 MHz, Methanol-
d4) δ 8.12 (s, 2H), 7.70 (m,
J = 4H), 7.11 (d,
J = 8.65 Hz, 2H), 6.98 (t,
J = 7.33 Hz, 2H), 3.91 (s, 2H);
[0144] 13C NMR (101 MHz, Methanol-
d4) δ 163.7, 157.8, 132.4, 124.6, 121.4, 116.0, 37.5;
[0145] HRMS (ESI+, DMSO, FT-ICR): m/z calcd. for C
16H
14InN
2O
2 ([M-Cl]
+) 381.00886, found 381.01022; calcd. for C
18H
20InN
2O
3S ([M-Cl+DMSO]
+) 459.02279, found 459.02408;
[0146] FT-IR (KBr pellete, cm
-1): 1618 (C=N).
Example 2
[0147] Complex 2 (Gaa1(s1
∗s5)): M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modifications
on two benzene rings of the salicylaldehyde residue are N-propargyl-N-methylamino
and diethylamino at position R3, respectively, and Z is chloride ion.
[0148] The complex 2 was prepared as described below.
[0149] 4-diethylaminosalicylic aldehyde and the maleonitrile diamine precursor were dissolved
in acetonitrile with a ratio of 1:1, and subsequently a small amount of sulfuric acid
was added dropwisely, and then the system was reacted under reflux at 90 °C for 24
h. After stopping the reflux, a large amount of ether was added to the system, so
that a dark purple solid was precipitated. Then, the precipitated solid was filtrated,
collected and washed with ether, and consequently the intermediate product a. was
yielded.
[0150] The intermediate product a., 4-N-propargyl-N-methylaminosalicylic aldehyde and gallium
trichloride were dissolved in acetonitrile with a ratio of 1:1:5, and reacted at 90
°C under reflux for 24 h. After stopping the reflux, a large amount of ether was added
to the system,so that a dark red solid was precipitated. Then, the precipitated solid
was filtrated, collected and washed with ether, and consequently the complex 2 was
yielded.
Characterization:
[0151] The complex 2 was characterized by the same methods as described in Example 1. The
results were shown as below:
1H NMR (400 MHz, DMSO-d6) δ 8.37 (d, J = 8.0 Hz, 1H), 8.26 (d, J = 7.3 Hz, 1H), 7.58-7.47
(m, 1H), 7.48-7.38 (m, 1H), 6.55 (t, J = 8.4 Hz, 1H), 6.47 (t, J = 8.9 Hz, 1H), 6.17
(d, J = 11.6 Hz, 1H), 6.06 (d, J = 12.0 Hz, 1H), 4.34 (s, 2H), 3.50 (q, J = 5.4 Hz,
6H), 3.12 (d, J = 4.1 Hz, 3H), 1.75 (s, 0H), 1.17 (t, J = 7.0 Hz, 7H).
Example 3
[0152] Complex 3 (Gaa1s1): M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen,
the modification on the benzene ring of the salicylaldehyde residue is diethylamino
at position R3, and D is chloride ion.
[0153] The complex 3 was prepared as described below.
[0154] The substituted salicylaldehyde, the diamine precursor and gallium trichloride corresponding
to complex 3 were placed in acetonitrile, and then reacted at 90 °C under reflux for
24 h. After stopping the reflux, ether was added to the system, so that a red solid
was precipitated. Then, the precipitated solid was filtrated, collected and washed
with ether, and consequently the complex 3 was yielded.

Characterization:
[0155] The structure of the complex 3 was characterized by hydrogen nuclear magnetic resonance
spectrum, carbon spectrum, high-resolution mass spectrometry and infrared spectroscopy,
and the photophysical properties of the complex 3 were characterized by ultraviolet-visible
absorption spectrometer and fluorescence spectrometer.
[0156] 1H NMR (400 MHz, Methanol-d4) δ 8.24 (s, 2H), 7.30 (d, J = 9.3 Hz, 2H), 6.53 (dd, J
= 9.3, 2.5 Hz, 2H), 6.22 (d, J = 2.4 Hz, 2H), 3.56 (q, J = 7.1 Hz, 8H), 1.26 (t, J
= 7.1 Hz, 12H);
13C NMR (101 MHz, Methanol-d4) δ 172.1, 158.3, 157.9, 139.5, 118.0, 112.1, 111.8, 108.9,
101.6, 46.3, 13.1;
HRMS (ESI+, DMSO, FT-ICR): m/z calcd. for C
28H
32GaN
4O
2 ([M-Cl]+) 525.17756, found 525.17923; calcd. for C30H38GaN2O3S ([M-CI+DMSO]+) 603.19149,
found 603.19322;
FT-IR (KBr pellete, cm
-1): 1616 (C=N).
Example 4
[0157] The complex 11 was prepared as follows:

[0158] The substituted salicylaldehyde, the diamine precursor and gallium trichloride corresponding
to complex 11 were placed in acetonitrile, and then reacted at 90 °C under reflux
for 24 h. After stopping the reflux, a large mount of ether was added to the system,
so that a yellow solid was precipitated. Then, the precipitated solid was filtrated,
collected and washed with ether, and consequently the pure complex 11 was yielded.
Characterization:
[0159] The structure of the complex 11 was characterized by hydrogen nuclear magnetic resonance
spectrum, carbon spectrum, high-resolution mass spectrometry and infrared spectroscopy,
and the photophysical properties of the complex 11 were characterized by ultraviolet-visible
absorption spectrometer and fluorescence spectrometer.
[0160] 1H NMR (400 MHz, Methanol-
d4) δ 8.82 (s, 2H), 7.88 - 7.70 (m, 2H), 7.42 - 7.14 (m, 4H), 6.38 (dd, J = 9.0, 2.5
Hz, 2H), 6.26 (d, J = 2.5 Hz, 2H), 3.50 (q, J = 7.0 Hz, 8H), 1.24 (t, J = 7.0 Hz,
12H);
13C NMR (101 MHz, Methanol-
d4) δ 163.7, 158.7, 153.3, 132.8, 128.5, 123.6, 108.0, 104.5, 99.1, 12.9;
HRMS (ESI+, DMSO, FT-ICR): m/z calcd. for C
28H
32GaN
4O
2 ([M-Cl]
+) 525.17756, found 525.17923; calcd. for C
30H
38GaN
2O
3S ([M-Cl+DMSO]
+) 603.19149, found 603.19322;
FT-IR (KBr pellete, cm
-1): 1616 (C=N).
Example 5
[0161] The complex 5 was prepared as follows:

[0162] The substituted salicylaldehyde, the diamine precursor and germanium trichloride
corresponding to complex 5 were placed in acetonitrile, and then reacted at 90 °C
under reflux for 24 h. After stopping the reflux, a large mount of ether was added
to the system, so that a red solid was precipitated. Then, the precipitated solid
was filtrated, collected and washed with ether, and consequently the pure complex
5 was yielded.
Characterization:
[0163] The structure of the complex 5 was characterized by hydrogen nuclear magnetic resonance
spectrum, carbon spectrum, high-resolution mass spectrometry and infrared spectroscopy,
and the photophysical properties of the complex 5 were characterized by ultraviolet-visible
absorption spectrometer and fluorescence spectrometer.
[0164] 1H NMR (400 MHz, Methanol-
d4) δ 8.24 (s, 1H), 7.30 (d, J = 9.4 Hz, 4H), 6.53 (dd, J = 9.3, 2.4 Hz, 4H), 6.22 (d,
J = 2.3 Hz, 4H), 3.84 (s, 6H);
13C NMR (101 MHz, Methanol-
d4) δ 164.3, 163.7, 158.8, 133.4, 125.8, 110.8, 107.0, 102.1, 55.8;
HRMS (ESI+, DMSO, FT-ICR): m/z calcd. for C
24H
26GeN
4O
6S
2 ([M-2Cl+2DMSO]
+) 604.05001, found 604.05185;
FT-IR (KBr pellete, cm
-1): 1620 (C=N).
Example 6
[0165] The complexes 4, 6-10, and 12-20 were prepared and characterized by using the same
or similar method as described in Examples 1-5. The structures and properties of these
complexes were summaried in the following table:
| Complex |
Description |
| 6 Gaa1s2 |
red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is dimethylamino at position R3,
and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Methanol-d4) δ 8.30 (s, 2H), 7.33 (d, J = 9.3 Hz, 2H), 6.58 (d, J
= 9.3 Hz, 2H), 6.23 (d, J = 2.4 Hz, 2H), 3.21 (s, 12H). |
| 7 Gaa1s3 |
red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is tetrahydropyrrole substituent
at position R3, and D is chloride ion. |
| Characterization: 1H NMR (400 MHz, Methanol-d4) δ 8.24 (s, 2H), 7.29 (d, J = 9.2 Hz, 2H), 6.43 (dd, J
= 9.1, 2.3 Hz, 2H), 6.10 (d, J = 2.3 Hz, 2H), 3.64 - 3.37 (m, 8H), 2.24 - 1.89 (m,
8H). |
| 13C NMR (101 MHz, DMSO) δ 170.5, 156.9, 155.6, 111.1, 108.4, 101.0, 48.4, 25.3. |
| 8 Gaa1s5 |
red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is N-propargyl-N-methylamino |
| at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, DMSO-d6) δ 8.37 (s, 2H), 7.52 (d, J = 9.2 Hz, 2H), 6.55 (dd, J = 9.1,
2.4 Hz, 2H), 6.19 (d, J = 2.4 Hz, 2H), 4.35 (s, 2H), 3.13 (s, 6H), 1.75 (s, 1H). |
| 9 Gaa3s1 |
yellow solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is diethylamino at position R3,
and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Methanol-d4) δ 8.82 (s, 2H), 7.88 - 7.70 (m, 2H), 7.44 - 7.13 (m,
4H), 6.38 (dd, J = 9.0, 2.5 Hz, 2H), 6.26 (d, J = 2.5 Hz, 2H), 3.50 (q, J = 7.0 Hz,
8H), 1.24 (t, J = 7.0 Hz, 12H). |
| 10 Gaa1s6 |
dark red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is a fused N-Methylthiomorpholine |
| at position R3/R4, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, DMSO-d6) δ 8.28 (s, 2H), 7.34 (d, J = 9.3 Hz, 2H), 6.55 (d, J = 9.3
Hz, 2H), 3.91 - 3.63 (m, 4H), 3.17 (s, 6H), 3.09 - 2.93 (m, 4H). |
| 13C NMR (101 MHz, DMSO) δ 163.8, 157.6, 152.0, 134.9, 130.2, 117.2, 110.2, 107.4, 105.8,
52.5, 41.0, 22.9. |
| 4 Gaa1s0 |
dark red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, there is no modification
on the benzene ring of the salicylaldehyde residue, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Methanol-d4) δ 8.93 (s, 2H), 7.76 - 7.62 (m, 4H), 7.11 (d, J = 8.6
Hz, 2H), 6.98 (t, J = 7.4 Hz, 2H). |
| 12 Gaa1s9 |
dark red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is a fused N-Methylthiomorpholine |
| at position R2/R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Methanol-d4) δ 8.23 (s, 2H), 7.15 (s, 2H), 6.28 (s, 2H), 5.49 (s,
2H), 3.90-3.79 (m, 4H), 3.18 (s, 4H), 3.06-2.95 (m, 6H). |
| 13 Gaa1snBu |
dark red solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is N-n-butyl-N methylamino |
| at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Chloroform-d) δ 8.14 (s, 2H), 7.07 (d, J = 9.2 Hz, 2H), 6.34 (dd,
J = 9.3, 2.4 Hz, 2H), 6.26 (d, J = 2.4 Hz, 2H), 3.29 -3.45 (m, 8H), 1.60-1.68 (m,
8H), 1.46-1.26 (m, 8H), 0.98 (t, J = 7.2 Hz, 12H). |
| 14 Gaa3s0 |
yellow solid; |
| M is gallium, L is acetonitrile, X is ortho-disubstituted benzene, Y is hydrogen,
there is no modification on the benzene ring of the salicylaldehyde residue, and D
is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Methanol-d4) δ 9.37 (s, 2H), 8.13 (dd, J = 6.3, 3.4 Hz, 2H), 7.65
(dd, J = 8.0, 1.8 Hz, 2H), 7.63 - 7.53 (m, 4H), 7.10 (dd, J = 8.6, 1.1 Hz, 2H), 6.92
(ddd, J = 8.0, 7.0, 1.1 Hz, 2H). |
| 15 Gaa7s1 |
orange solid; |
| M is gallium, L is acetonitrile, X is 3,4-disubstituted pyridine, Y is hydrogen, the
modification on the benzene ring of the salicylaldehyde residue is diethylamino at
position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Chloroform-d) δ 8.96 (d, J = 13.8 Hz, 2H), 8.86 (s, 1H), 8.33 (d,
J = 5.6 Hz, 1H), 7.77 (d, J = 5.7 Hz, 1H), 7.35 (t, J = 8.1 Hz, 2H), 6.47 (dd, J =
19.1, 9.0 Hz, 2H), 6.25 (d, J = 3.0 Hz, 2H), 3.54 (p, J = 7.4 Hz, 8H), 1.26 (td, J
= 7.0, 3.6 Hz, 12H). |
| 16 Gaa7s3 |
orange solid; |
| M is gallium, L is acetonitrile, X is 3,4-disubstituted pyridine, Y is hydrogen, the
modification on the benzene ring of the salicylaldehyde residue is a tetrahydropyrrole
substituent at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Chloroform-d) δ 9.01 (s, 1H), 8.86 (d, J = 12.8 Hz, 2H), 8.41 (d,
J = 6.6 Hz, 1H), 8.10 (d, J = 6.6 Hz, 1H), 7.36 (dd, J = 14.8, 9.1 Hz, 2H), 6.54 (d,
J = 9.3 Hz, 1H), 6.42 (d, J = 9.1 Hz, 1H), 6.11 (d, J = 2.3 Hz, 2H), 3.57 (d, J =
46.4 Hz, 8H), 2.10 (d, J = 6.5 Hz, 8H). |
| 17 Gaa0s1 |
light yellow solid; |
| M is gallium, L is acetonitrile, X is -CH2-CH2-, Y is hydrogen, the modification on the benzene ring of the salicylaldehyde residue
is diethylamino at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Chloroform-d) δ 9.01 (s, 1H), 8.86 (d, J = 12.8 Hz, 2H), 8.41 (d,
J = 6.6 Hz, 1H), 8.10 (d, J = 6.6 Hz, 1H), 7.36 (dd, J = 14.8, 9.1 Hz, 2H), 6.54 (d,
J = 9.3 Hz, 1H), 6.42 (d, J = 9.1 Hz, 1H), 6.11 (d, J = 2.3 Hz, 2H), 3.57 (d, J =
46.4 Hz, 8H), 2.10 (d, J = 6.5 Hz, 8H). |
| 18 Gaa4s1 |
orange solid; |
| M is gallium, L is acetonitrile, X is 4-cyano ortho-disubstituted benzene, Y is hydrogen,
the modification on the benzene ring of the salicylaldehyde residue is diethylamino
at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, DMSO-d6) δ 8.92 (d, J = 9.7 Hz, 2H), 8.34 (d, J = 1.7 Hz, 1H), 7.99
(d, J = 8.7 Hz, 1H), 7.69 (dd, J = 8.6, 1.6 Hz, 1H), 7.33 (dd, J = 12.8, 9.1 Hz, 2H),
6.40 (ddd, J = 8.6, 5.6, 2.4 Hz, 2H), 6.04 (d, J = 2.4 Hz, 2H), 1.17 (t, J = 7.0 Hz,
12H). |
| 19 Gaa5s1 |
orange solid; |
| M is gallium, L is acetonitrile, X is 4,5-dicyano ortho-disubstituted benzene, Y is
hydrogen, the modification on the benzene ring of the salicylaldehyde residue is diethylamino
at position R3, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, DMSO-d6) δ 8.95 (s, 2H), 8.52 (s, 2H), 7.31 (d, J = 9.1 Hz, 2H),
6.45 (dd, J = 9.2, 2.4 Hz, 2H), 6.03 (s, 2H), 3.49 (q, J = 7.0 Hz, 8H), 1.18 (t, J
= 7.0 Hz, 12H). |
| 20 Gaa1s8 |
orange solid; |
| M is gallium, L is acetonitrile, X is -C(CN)=C(CN)-, Y is hydrogen, the modification
on the benzene ring of the salicylaldehyde residue is a fused 3,3-dimethylcyclohexane
at position R2/R3 and position R3/R4, and D is chloride ion. |
| Characterization: |
| 1H NMR (400 MHz, Chloroform-d) δ 8.10 (s, 2H), 7.04 (s, 2H), 3.51 (t, J = 6.2 Hz,
4H), 3.39 (t, J = 5.8 Hz, 4H), 1.79 (t, J = 5.9 Hz, 4H), 1.74 (t, J = 6.3 Hz, 4H),
1.65 (s, 12H), 1.28 (s, 12H). |
Experiments
Experiment 1
[0166] Activity test experiment and results for the complexes:
The cell lines used in the experiment were obtained from Peking University. The cells
were cultured in a cell incubator containing 5% CO
2 under the atmosphere of saturated steam at a constant temperature of 37 °C. The medium
used was a high-sugar Dulbecco's modified Eagle's medium containing 10% fetal bovine
serum, 100 µg/mL penicillin and 100 U/mL streptomycin. The cells were grown in a six-well
culture plate and passaged every other day. The cytotoxicity of the complex was evaluated
by the CCK-8 kit, in which the cells were passed to a 96-well plate containing about
25,000 of cells and 200 µL of medium in each well. After the cells had grown stably
and adherently, the medium was changed to complete mediums with different concentrations
of the complex to be detected, and a 3-well parallel experiment was performed for
each concentration. After culturing in the incubator for 24 hours, the medium was
removed and the cells were washed with 100 µL of PBS buffer (pH = 7.4) for 3 times.
Subsequently, 100 µL mixture of 10% CCK-8 solution and 90% serum-free medium was added
into both the test wells and the control wells, and then was placed in an incubator
for culturing. After about 1 hour, the absorption of 450 nm wavelength light in the
test and control wells were measured by using a microplate reader, and the cell viabilities
(CV) under different concentrations of the complex were calculated according to the
following formula:

in which A is the absorption value of 450 nm wavelength light; the subscript s represents
the well to be tested with sample, c represents the live cell control well without
sample, and b represents the blank control well without sample and cells. A cytotoxicity
curve based on the obtained cell viabilities under different concentrations of the
complex was drawn, and the median lethal concentration IC
50 of the complex against the cell line then could be read out from the drawing.
[0167] By the aforementioned method, the toxicity of the complexes against HeLa cell line
were preliminarily screened. The cytotoxicity curve of the complex 1 against the human
cervical cancer cell line HeLa was shown in Figure 2. Then, the experiments about
the toxicity selectivity of the complexes among multi-cell lines were performed. The
results were shown in Figure 1, in which A375 was a human malignant melanoma cell
line, A549 was a human non-small cell lung cancer cell line, SW480 was a human colorectal
cancer cell line, and MCF7 was an in situ ER-positive human breast cancer cell line.
It could be seen from Figure 1 that the median lethal concentrations of the complexes
1, 11 and 5 in 24 hours against different cell lines were at the level of 0.1 nM to
2 µM, which demonstrated that these complexes have obvious killing effect against
the cancer cells.
[0168] Meanwhile, the complex 3 (3#) prepared in Example 3 and cisplatin were subjected
to the control experiments about the toxicity selectivity among multi-cell lines by
the above method. The cell lines used were Hela, HepG2 liver cancer cell lines, A375,
MCF7, MOLT-4 acute lymphoblastic leukemia cells, MDA-MB-231 highly metastatic breast
cancer cell line, A549, HEK293 human renal epithelial cell line, COS7 renal epithelial
cells, DU145 prostate cancer cells, Raw264.7 monocyte giant Phages. The results were
shown in Table 1
(in vitro Cytotoxicity of
3 and cisplatin against different cell lines) below.
Table 1: in vitro Cytotoxicity of
3 and cisplatin against different cell lines
| |
IC50a/µM |
| HeLa |
HepG2 |
A375 |
MCF7 |
MOLT-4 |
MDA-MB-231 |
| 3# cisplatin |
1.6±0.1 |
1.3±0.5 |
1.2±0.3 |
2.7±0.5 |
0.9±0.1 |
5.2±0.9 |
| 5.3±0.3 |
5.3±0.1 |
3.4±0.3 |
9.1±0.9 |
2.0±0.2 |
27.0±1.3 |
| |
A549 |
DU145 |
HEK293 |
COS7 |
Raw264.7 |
|
| 3# |
0.8±0.1 |
0.8±0.1 |
0.7±0.1 |
1.6±0.6 |
3.2±0.1 |
|
| cisplatin |
9.4±1.5 |
2.7±0.1 |
2.0±0.1 |
6.7±0.6 |
10.1±1.2 |
|
[0169] It could be seen from Table 1 that, the median lethal concentration of the complex
3 in 24 hours against different cell lines were at the level of 0.1 nM to 2 µM, which
demonstrated that the complex 3 has obvious killing effect against the cancer cells
compared to cisplatin.
Experiment 2
Cell culture and measurement of cytotoxicity
[0170] The cell lines used in the experiments were obtained from Peking University. The
cells were cultured in a cell incubator containing 5% CO
2 under the atmosphere of saturated steam at a constant temperature of 37 °C. The medium
used was a high-sugar Dulbecco's modified Eagle's medium containing 10% fetal bovine
serum, 100 µg/mL penicillin and 100 U/mL streptomycin. The cells were grown in a six-well
culture plate and passaged every other day. The cytotoxicity of the complex was evaluated
by the CCK-8 kit, in which the cells were passed to a 96-well plate containing about
25,000 of cells and 200 µL of medium in each well. After the cells had grown stably
and adherently, the medium was changed to complete mediums with different concentrations
of the complex to be detected, and a 3-well parallel experiment was performed for
each concentration. After culturing in the incubator for 24 hours, the medium was
removed and the cells were washed with 100 µL of PBS buffer (pH = 7.4) for 3 times.
Subsequently, 100 µL mixture of 10% CCK-8 solution and 90% serum-free medium was added
into both the test wells and the control wells, and then was placed in an incubator
for culturing. After about 1 hour, the absorption of 450 nm wavelength light in the
test and control wells were measured by using a microplate reader, and the cell viabilities
(CV) under different concentrations of the complex were calculated according to the
following formula:

in which A is the absorption value of 450 nm wavelength light; the subscript s represents
the well to be tested with sample, c represents the live cell control well without
sample, and b represents the blank control well without sample and cells. Based on
the obtained cell viabilities under different concentrations of the complex in Examples
1-6, A cytotoxicity curve was drawn, and the median lethal concentration IC
50 of the complex against the cell line then could be read out from the drawing.
[0171] The safety index (SI) was calculated according to the following equation:

[0172] The cell lines used were HeLa, HepG2, MCF7, SW480, A375, A549, normal colonic epithelial
cells NCM460, human microglia CHEM5 and human umbilical vein endothelial cells HUVEC.
[0173] The results were shown in Table 2
(In vitro anticancer activities of complexes) below.
Table 2. In vitro anticancer activities of complexes.
a
| Complex |
C50(µM) |
SIb |
| Hela |
HepG 2 |
MCF7 |
SW480 |
A375 |
A549 |
NCM460 |
CHEM 5 |
HUVEC |
|
| 1# |
17.23 |
29.54 |
46.79 |
26.67 |
11.11 |
27.19 |
87.23 |
52.05 |
114.98 |
6.37 |
| 5# |
39.17 |
48.21 |
181.79 |
68.99 |
36.12 |
50.92 |
134.37 |
169.38 |
187.38 |
4.78 |
| 3# |
0.70 |
1.25 |
0.42 |
1.13 |
0.30 |
0.16 |
0.55 |
0.87 |
1.32 |
1.89 |
| 13# |
21.48 |
20.87 |
1.74 |
4.10 |
0.90 |
2.72 |
20.61 |
2.28 |
3.50 |
0.16 |
| 14# |
19.53 |
38.64 |
53.00 |
257.49 |
23.97 |
76.47 |
211.88 |
65.12 |
162.76 |
8.33 |
| 10# |
87.67 |
72.65 |
61.72 |
451.41 |
91.19 |
124.15 |
321.90 |
51.87 |
332.39 |
3.79 |
| 9# |
12.36 |
46.15 |
34.78 |
4.89 |
1.37 |
1.22 |
33.45 |
1.81 |
9.33 |
0.75 |
| 8# |
259.81 |
291.42 |
190.18 |
572.17 |
228.60 |
138.82 |
71.02 |
236.34 |
203.07 |
0.78 |
| 4# |
75.29 |
43.49 |
134.36 |
0.59 |
2.20 |
1.16 |
27.66 |
1.64 |
6.37 |
0.08 |
| 6# |
1.38 |
7.75 |
0.47 |
4.85 |
0.07 |
1.38 |
6.44 |
2.27 |
4.09 |
0.64 |
| 11# |
0.97 |
0.92 |
0.24 |
4.10 |
0.67 |
2.72 |
1.72 |
0.82 |
1.38 |
1.42 |
| 12# |
45.82 |
34.55 |
43.51 |
42.60 |
10.82 |
39.28 |
89.87 |
44.66 |
58.90 |
1.29 |
| 2# |
6.35 |
8.19 |
5.29 |
2.20 |
0.83 |
2.29 |
4.26 |
2.82 |
1.88 |
0.30 |
| 7# |
8.61 |
10.30 |
14.20 |
7.58 |
1.40 |
3.56 |
23.08 |
5.71 |
2.47 |
0.30 |
| 15# |
97.42 |
89.67 |
203.82 |
32471 |
214.64 |
272.87 |
339.56 |
298.49 |
75.78 |
0.78 |
| a IC50 was measured by method of MTT. |
[0174] It can be seen that, a plurality of complexes show the anti-cancer activity against
different cancer cell lines, and among them, 3# and 11# complexes show the greatest
anti-cancer activity against many cancer cell lines, with IC
50 values much lower than other complexes. In addition, the safety indexes of 3# and
11# complexes against HUVEC cells were 1.89 and 1.42, respectively, and that is to
say, they had lower cytotoxicity to normal cells. The results showed that 3# and 11#
complexes have significant applicability in cancer treatment.
Experiment 3
Cell imaging experiment
[0175] The instrument used for living cell fluorescence imaging is Nikon A1 R-si laser scanning
confocal fluorescence microscope (Japan). The cells were transplanted and attached
on a round cover glass treated with 0.1 mM polylysine, and then placed in a complete
medium to be cultured for 24 hours. After that, the cells were treated with a sample
of the complex to be tested. The treated living cell sample was rinsed twice with
phosphate buffer solution and then placed under a microscope for imaging. Instrument
parameters were as follows: the objective lens was a 60x oil lens, the imaging resolution
was 1024×1024, and the scanning speed was 0.5 frames per second. Excitation light
and detectors with different wavelengths were used for detection during imaging.
[0176] Particularly, the complex 3 prepared in Example 3, 488 nm laser excitation, and 585/65
detector channel were used.
[0177] The results were shown in Figure 3. Fig.3(1) was a fluorescence distribution diagram
of the complex 3 in the cells, Fig.3(2) was a fluorescence distribution diagram of
the commercially available mitochondria labeling, Fig.3(3) was the overlapped diagram
of Fig.3(1) and Fig.3(2), and Fig.3(4) was an image of cells without fluorescence
distribution. It can be seen that the complex 3 was mainly distributed in mitochondria
of the cells, and when accumulating on tumor sites, it was also distributed in mitochondria
of the tumor cells.
Experiment 4
In vivo experiments in mice
In vivo fluorescence experiment:
[0178] HeLa (1.5 x 10
6) was transplanted around the hip joint of 6-week-old male nude mice to form transplanted
tumors. After the tumors had grown up to about 200 mm
3, the dosing solutions of the complex 3 (3#) in Example 3 and the complex 11 (11#)
in Example 4 with different concentrations prepared by adding saline were injected
into the mice through tail vein with a dosage of 1.4-6.4 mg/kg. At multiple points
during a period from 5 minutes to 72 hours after the injection, in vivo imaging was
performed to observe the distribution of the complex 3 in mice and the location of
tumors. The instrument used was in vivo imaging system of Xenogen (Caliper Life Sciences,
Hopkinton, MA, USA), with the imaging parameters of 500nm excitation and 560-620 detector
channel. After 72 hours, the nude mice was dissected, and the main organs were taken
out and placed under the imaging system for imaging using the same parameters to observe
the distribution of the complexes in each organ.
[0179] As shown in Fig.4A, still a lot of the complex 3 and the complex 11 accumulated in
the tumor tissue 72 hours after the injection. Figs. 4B and 4C showed the accumulation
of complexes in the major organs, i.e., heart, liver, spleen, lung and kidney, and
it can be seen that, the accumulation of the complex 3# and the complex 11# in the
liver was much higher than that in other organs, and in contrast, there was almost
no accumulation in the heart and the spleen.
[0180] Additionally, the concentration of the complex 3# or 11# in the major organs was
measured by ICP-MS (inductively coupled plasma mass spectrometer). The concentrations
of 3# and 11# complexes in tumor tissues were 8.84 and 9.55 µg/g, respectively, which
were higher than those in the heart, spleen, lung and kidney, indicating that the
complexes could accumulate in tumor tissues, which was consistent with the fluorescence
images.
Experiment 5
In vivo tumor suppression experiment:
[0181] Nude mice carrying HeLa tumors were divided into 4 groups, each with 8 mice. After
growing up to about 200 mm
3, the tumors were treated with cisplatin, the complex 3 prepared in Example 3, and
the complex 11 prepared in Example 4, respectively, to set a tumor control group.
The dosage was 4 µmol/kg, and the administration frequency was once every 2 days.
The volume of the tumor was calculated with the length and width of the tumor according
to the following formula:

[0182] After 21 days, the nude mice of each group were died and dissected. The tumor inhibition
was calculated according to the following formula:

in which Wc and Wt were the masses of the tumors in the control group and the experimental
group, respectively.
[0183] The curves about the changes of the tumor volume and mass after treatment were shown
in Figs. 5A and 5B. It can be seen that the therapeutic effect of the complex 11#
was better than that of the complex 3#. The volume and mass of the tumor after treated
with the complex group were always smaller than those treated with the cisplatin group.
That is to say that, the experimental group was better than the control group.
[0184] As shown in Figs. 7D, 7E and 7F, free complexes 3# and 11# significantly inhibited
the growth of tumors. After 21 days of treatment, the tumor inhibitions of the complexes
3# and 11# were 56.8% and 84.6%, respectively. The tumor inhibition of cisplatin was
29.9%. The results showed that the free gallium complexes 3# and 11# have better anti-tumor
effects than that of free cisplatin.
[0185] Meanwhile, it can be seen from Fig.6 that the weight of nude mice did not change
significantly during the treatments in all of the groups, indicating that these treatments
could be tolerated very well and there was no any acute side effects occurred during
the treatments.
[0186] Additionally, the histological changes of tumor tissues were checked by H&E staining.
As shown in Figs. 7D, tumor tissues showed different degrees of necrosis after treatments,
and the treatment effects of the complexes were better than that of cisplatin.
[0187] The blood samples were collected for hematological analysis to study the effects
of cisplatin and the complexes 3# and 11# on liver and kidney function of nude mice.
The research indicators included alanine aminotransferase (ALT), urea nitrogen (BUN),
triglycerides (TG), creatine kinase (CK), aspartate aminotransferase (AST), creatinine
(CREA), high Density lipoprotein (HDLC), and lactate dehydrogenase (LDH).
[0188] The kidney function was related to the blood indicators of BUN and CREA and the liver
function. The results about alanine aminotransferase (ALT) and aspartate aminotransferase
(AST) in the blood of nude mice were shown in Fig. 8. As shown, cisplatin could cause
the acute toxicity against the liver and the kidney, and in constrast, the complexes
3# and 11# could significantly reduce the damage of cisplatin or tumors to the kidney
and liver function, so that the blood biochemical indicators returned to the health
level.
[0189] Further, the parts such as heart, spleen, lung, liver, and kidney were subjected
to the H&E staining analysis.
[0190] As shown in Fig.9, under the experimental conditions, no significant pathological
changes were found in the heart, spleen and lungs. However, liver edema and degeneration
and kidney swelling were observed in the cisplatin treatment group. In contrast, in
the complexes 3# and 11# groups, no damage of kidney and only slight damage of liver
occurred. The results indicated that the potential toxic side effects of the complexes
were lower than that of cisplatin.
[0191] These results further confirm that the gallium complexes 3# and 11# have higher safety
and application potential than cisplatin.
[0192] The present invention has been described in detail in combination with the embodiments
and the examples above, but these descriptions should not be understood as the limits
to the present invention. Those skilled in the art should understand that, without
departing from the spirit and scope of the present invention, various equivalent substitutions,
modifications or improvements can be made to the technical solutions of the present
invention and its embodiments, and all of these fall within the scope of the present
invention. The protection scope of the present invention is subject to the appended
claims.
1. A main group metal complex having the structure represented by Formula I or Formula
II as below, or pharmaceutically acceptable salt, solvate, non-covalent bond compound
or prodrug thereof,

wherein the main group metal complex, including its cation, is composed of planar
tetradentate Schiff base ligands and p-block main group metal ions.
2. The main group metal complex according to claim 1, characterized in that,
wherein, M represents the p-block main group metal;
X represents a diamine residue, and nitrogen atoms on each side of its imine bond
are connected by substituted or unsubstituted C1-12 alkyl or C2-12 alkenyl, or X exists as ortho-substituents of a substituted or unsubstituted aryl
or heterocyclic aryl;
Y is hydrogen, C1-12 alkyl, halogen, halogen-substituted alkyl, cyano, amino, carbonyl, C1-12 alkoxy or
substituted amino;
Z is hydrogen, C1-12 alkyl, halogen, nitro, hydroxyl, mercapto or carboxyl;
R1, R2, R3 and R4 are substituents on the benzene ring of the corresponding ligand, and are each independently
selected from hydrogen, halogen, nitro, hydroxyl, mercapto, carboxyl, amino, cyano,
C1-12 alkyl, C2-12 alkenyl, C2-12 alkynyl, C1-8 alkoxy, C2-8 alkenyloxy, C2-8 alkynyloxy, C1-8 alkylthio, C3-8 heterocyclyl, aryl, C1-8 alkanoyl, C1-8 alkamido, C1-8 alkylsulfonyl, arylsulfonyl, C1-12 alkyl substituted amino or halogen substituted C1-12 alkyl, or two adjacent substituents among R1, R2, R3 and R4 (R1 and R2, R2 and R3 and/or R3 and R4) may form a ring.
3. The main group metal complex according to claim 1 or 2, characterized in that,
wherein M in Formula I or Formula II is one of aluminum, gallium, indium, thallium,
germanium or tin, preferably is one of aluminum, gallium, indium, thallium or germanium,
and most preferably is one of aluminum, gallium, indium or germanium;
nitrogen atoms on each side of X are connected by C1-5 aliphatic chain or substituted aliphatic chain, or X exists as ortho-substituents
of an aromatic ring; preferably, X in Formula I or Formula II is selected from -CH2-, -CH2-CH2-, -CH(CH3)-CH2-, -CH(CN)-CH(CN)-, -CH(CN)-CH2-, -CH2(Cl)-CH(CN)-, -CH2(OH)-CH(CN)-, -CH2(Cl)-CH2-, - CH2(OH)-CH2-, -CH=CH-, -CO-CH(CN)-, -C(CN)=C(CN)-, -CH=C(CN)-, -CH=C(Cl)-, - CH=CH-CH=CH-, -CH=C(CN)-CH=CH-,
-CH=C(NH3)- or -CO-CH2-, or exists as ortho-disubstituted group of substituted or unsubstituted benzene,
naphthalene, anthracene, phenanthrene, pyridine, imidazole, pyrrole, thiophene, furan,
benzopyrrole or benzofuran; when being a cyclic group, X is connected to the imino
group of the corresponding ligand through two adjacent atoms on the cyclic backbone;
Y in Formula I or Formula II is hydrogen, halogen, cyano, C1-4 alkyl or C1-4 alkoxy, and preferably is hydrogen, halogen, cyano, methyl, ethyl, isopropyl, methoxy,
ethoxy, halogen-substituted C1-3 alkyl or halogen-substituted C1-3 alkoxy;
R1, R2, R3 and R4 are each independently selected from hydrogen, halogen, nitro, hydroxyl, mercapto,
carboxyl, amino, cyano, C1-12 alkyl, C2-12 alkenyl, C2-12 alkynyl , C1-8 alkoxy, C2-8 alkenyloxy, C2-8 alkynyloxy, C1-8 alkylthio, C3-8 heterocyclyl, aryl, C1-8 alkanoyl, C1-8 alkamido, C1-8 alkylsulfonyl, arylsulfonyl, N,N-bis(C1-6 alkyl)amino, N-(C1-6 alkyl)-N-(C1-6 alkyl)amino, N-(C1-6 alkyl)-N-C1-6 alkynyl)amino, N,N-diarylamino, N-(C1-6 alkyl)-N-arylamino, N-(C1-6 alkyl) -N-heterocyclylamino, -CF3-, -ClCH2-, -ClCH2-CH2-, (CH3)2C(CH2Cl)-, CH2-CH2Cl-CH(CH3)2- or halogen substituted C3-6 cyclic alkyl group including halogen-substituted cyclohexyl, halogen-substituted
cyclopentyl, and halogen-substituted methylcyclopentyl.
4. The main group metal complex according to any one of claims 1 to 3,
characterized in that,
wherein the main group metal complex further has a ligand represented by Formula III
or Formula IV as below:

wherein M represents the p-block main group metal;
X represents a diamine residue, and nitrogen atoms on each side of its imine bond
are connected by C
1-5 aliphatic chain or substituted aliphatic chain, or X exists as ortho-substituents
of an aromatic ring;
Y is hydrogen or alkyl;
R
1, R
2, R
3 and R
4 are each independently selected from hydrogen, halogen, nitro, hydroxyl, amino, substituted
amino, alkyl, alkoxy, halogen-substituted alkyl, mercapto or alkylthio, and two adjacent
substituents, i.e. R
1 and R
2, R
2 and R
3 and/or R
3 and R
4 may form a ring;
L represents one or more axial monodentate ligands selected from halogen, oxygen coordinating
small molecule or nitrogen coordinating small molecule;
Z is hydrogen or alkyl;
wherein L preferably represents one or more axial monodentate ligands including anionic
ligands and neutral ligands; and L may also be a non-coordinating anion; the anionic
ligands preferably include halogen ions such as fluorine, chlorine, bromine, iodide
ions, and acetate ions; the neutral ligand is an oxygen coordinating or nitrogen coordinating
ligand, preferably a solvent molecule, such as MeCN, MeOH, DMSO, DMF;
preferably, the main group metal complex (including cationic type) includes:
5. A method for preparing the main group metal complex according to any one of claims
1 to 4,
characterized in that,
a salicylaldehyde or substituted salicylaldehyde represented by Formula V, a diamine
precursor represented by Formula VI, and a main group metal salt MD are added in an
organic solvent L, and the reaction is carried out at a temperature ranging from 50
to 150 °C for 12 to 24 h, and then the product represented by Formula III is obtained:
6. A method for preparing the main group metal complex according to any one of claims
1 to 4,
characterized in that,
the product represented by Formula IV can be produced according to the following reaction
scheme, in which a ligand represented by Formula VII and a main group metal salt MD
are added in an organic solvent L, and the reaction is carried out at a temperature
ranging from 50 to 150 °C for 12 to 24 h, and then the target complex molecule is
obtained in one step:
7. A pharmaceutical composition using the main group metal complex according to any one
of claims 1 to 4 as an active ingredient, comprising pharmaceutically acceptable excipients.
8. A pharmaceutical preparation containing the main group metal complex according to
any one of claims 1 to 4, which can be administrated through gastrointestinal tract
or by injection,
wherein the preparations administrated through gastrointestinal tract include tablets,
capsules, oral solutions, oral emulsions, suppositories and granules; and
the preparations administrated by injection include injection solutions, injection
emulsions, injection sustained-release solutions and injection suspensions.
9. A use of the pharmaceutical composition or preparation containing the main group metal
complex having the structure represented by Formula I or Formula II, or pharmaceutically
acceptable salt, solvate, non-covalent bond compound or prodrug thereof in preparing
drugs against cancers, including breast cancer, liver cancer, lung cancer, melanoma,
prostate cancer, colon cancer, colorectal cancer, glioblastoma, kidney cancer, pancreatic
cancer, gastric cancer, lymphoma, cervical cancer, ovarian cancer, esophageal cancer,
nasal cancer, leukemia, breast duct cancer, gallbladder cancer, testicular cancer,
cardia cancer and thyroid cancer,
wherein the drugs are adminstated at a dosage of 0.01 to 200 mg/kg body weight per
day or 0.5 to 14 g to each patient per day.
10. A use of the main group metal complex having the structure represented by Formula
I or Formula II, or pharmaceutically acceptable salt, solvate, non-covalent bond compound
or prodrug thereof in optical labeling, especially fluorescent labeling, and preferably
in fluorescence imaging, targeted preparations, administation monitoring, luminescent
materials, organic light-emitting diodes, and dye-sensitized solar cells.